A: 孙壕请一盘青岛大虾呗
A题比较容易,因为范围只有10,所以暴力搜索一下就好了,简单递归题
1 #include<cstdio> 2 #include<cstring> 3 int dfs(int n, int m, int num){ 4 if(n == 0 && m == 0 && num == 0){ 5 return 1; 6 } 7 if(n == -1 || m == -1 || num == 0) return 0; 8 return dfs(n-1, m, num << 1) + dfs(n, m-1, num-1); 9 } 10 int main(){ 11 int n, m; 12 while(scanf("%d%d", &n, &m) != EOF){ 13 printf("%d\n", dfs(n, m, 2)); 14 } 15 }